The deployment is the moment you place the sensor in the ground. This is the moment the sensor gets in touch with the soil and starts collecting meaningful data.
The activation is the moment you activate the sensor. This is the moment the data from the sensor is displayed to you on the Cital Insights Platform. Any data from before that moment in time will not be visible to you. The data not displayed is not lost, however. By modifying the activation timeframe, you can display data that was previously hidden.